Tape-cutting mechanism for sewing-machines.



w[ L. BARRON.

TAPE CUTTING MECHANISM FOR SEWING MACHINES.

APPLICATION HLED MAYH,1914.

11 ,,%%%,,5U1 Patented Feb. 5, 1,918.

WILLIAM L. BARRON, OF NEW YQRK, N Y ASSIGINOH. TO THE SINGER MANUFAC- TUBING COMPANY, A CORPORATION 013 NEW JERSEY.

TAPE-CUTTING MEGHANISM FOE, SEWING-MAUHINES.

1,255.,5tl1l.

To all whom it may concern:

Be it known that 1, WILLIAM L. Bnnnon, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certam new and useful Improvements in Tape-Cut ting Mechanisms for Sewing-Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This. invention relates to tape-cutting mechanism for sewing machines, and has for its'object to provide an efficient, durable and compactly arranged construction adapted to sever the tape at-the right point, and to moveforward a new supply of tape for engagem'ent by the stitch-forming mechanism of the sewing machine. The improvements are intended primarily for use in connection with sewing machines for sewing stay-tapes on the uppers of shoes, and on other articles requiring stays.

The improvements comprise a vertically disposed cutter-blade secured upon a carrier mounted to slide between spaced bracketarms projecting upwardly from a supporting bracket secured in fixed position upon the sewing machine frame. A guide-arm projects laterally from the cutter-blade carrier and abuts the inner face of one of said bracket-arms, and a slide-plate secured to the cutter-blade carrierabuts the outer faces ofthe bracket arms, so that the carrier is held against lateral movement. A treadle operated lever is employed to actuate the cutter-blade, said lever having a fulcrum upon the sewing machine frame and being connected to a link which is pivotally secured to the cutter slidelate. The cutter actuating-lever is operate against the pressure of a spring which serves normally to hold the cutter-blade depressed. The tape is fed between relatively adjustable guidelingers secured upon the forwardly projecting portion of the sewing machine throat-plate, which also supports an overlying springpressed ledger-blade. The throat-plate is formed with a longitudinal slot to receive the upwardly extending pointed end of a feeding pawl, the latter being pivotally supported upon a rock-arm projecting from a rock-shaft journaled in bearings afiorded by the sewing machine frame, said rock-shaft carrying at its outer end a short crank-arm. The said cranksarm is positioned between a lug on the cutter slide-plate and anadjust- Specification of Letters Eatent.

Patented Feb. 5, 19m.

Application filed ma 11, me Serial no. semen.

able finger on said plate, whereby operative movements are imparted to the tape feeding pawl from the cutter actuating mechanism, the arrangement being such that the pawl is advanced to feed the tape immediately after the retraction of the cutter-blade, a reverse movement of the pawl taking place as the 5 is a detail perspective view of the throat-- plate, the tape-guiding fingers carried thereby, and other connected parts.

The improvements are shown applied to a sewing machine formed with the bed-plate A, standard B and overhanging arm C. Projecting through the standard B and supported by suitable bearings therein is the main-shaft 1 from which operative movements are imparted to the needles 2, feeddog 3, and the usual loop-seizing members, through suitable intermediaries.

Rising from the bed-plate A are the supporting arms A", and secured in fixed position upon the upper surfaces of said arms is the throat-plate 4, the latter being provided with an enlarged front extension 4 which afi ords a support for the tape and the guiding elements therefor. Upon the upper face of the throat-plate extension is secured by means of screws 5, a cross-bar 6 formed with a channel in its lower face immediately over the beveled portion 7 of the throat-plate, so

that a tape-receiving slot is provided with opposed edge-guiding walls. To compensate forchanges in the width of the tape, two positioning or guiding fingers 8 are secured upon the upper face of the throat-plate, the i said fingers being held in their adjusted posi tion by means of screws 9.

At the rear of the guiding fingers 8, and formed in the throat-plate transversely thereof, is a slot 10, which is adapted to receive the cutter-blade 11 which cooperates in its tape severing operations with a ledgerblade 12, the latter having inclined edges fitted in corresponding guide-ways 13* formed in the parallel gibs 13, the latter being secured upon the throat-plate extension by means of screws 14 and being cut away adjacent the hubs of the guiding fingers 8. A light coiled spring 15 is fitted within a socket formed in the rear face of cross-bar 6 and acts to press the ledger-blade into engagement with a projecting guidefinger 11 of'the cutter-blade 11, whereby the two blades are accurately positioned for effective action upon the tape, the guide-- slide between the spaced arms 19" of abracket 19 secured in fixed osition upon the sewing machine frame by means of screws 20. A guide-arm 16 projects laterally from the carrier and abuts the inner face of one of the bracket-arms, and a slide plate 21 fixed to the carrier abuts the outer faces of the bracket-arms, so that the carrier is held against lateral movement and the cutter-blade is maintained in proper position.

The actuating members for the cutter comprise a treadle-actuated lever 22, fulcrumed at 23 to the sewing machine frame and provided with a bifurcated end 22 which embraces the lower end of a link 24, the two members being pivotally connected by means of stud-screw 25 and the link being secured to slide-plate 21.by means of the screw 26. A spring 27 is applied to the lever 22 and acts normally to depress the link 2& and to maintain the cutter-blade in its lower position. The lever 22 may be operated by any suitable means as, for example, a treadle connected to the rod R.

The movements of the cutter mechanism are utilized to operate a feeding device for the tape. The said device comprises a roekarm 28 provided with a sleeve 28 clamped, by means of clamping screw 29, upon a rockshaft 30 journaled in one of the supporting arms A". The upper end of rock-arm 28 is forked to receive the apertured shank of a feeding pawl 31 which is pivotally mounted upon a stud-screw 32 held in said arm. The pointed end of the pawl is normally pressed into engagement with the tape resting upon the throat-plate extension, by means of a light spring 33, one end of said spring being clamped under the head of a screw 341, which enters an aperture in the rock-arm 28, and the opposite end of the spring being fitted within an aperture formed in a lug 35 projecting downwardly from the pawl 31. To the outer end of rock-shaft 30 is secured a short crank-arm 36 which is positioned between a lug 37 on slide-plate 21 and the projecting finger 38 of an adjustable arm 38, the latter being formed with a longitudinal slot adapted to receive the shank of, clamping screw 39 by means of which the arm is held in its adjusted position.

It will be seen that the upward movement of slide-plate 21, under the influence of lever 22, will carry the finger 38 into engagement with crank-arm 36, and that the latter will act to retract the feeding pawl 31 simultaneously with the cutting movement of the blade 11, the extent of said movement being limited by a stop-screw c on one of the bracket-arms 19. When the lever 22 is released, the pressure of spring 27 thereon will exert a pull upon slide-plate 21 which moves downwardly to retract the cutterblade. When the sharpened inclined edge of the latter passes below the upper face of the throat-plate, the lug 37 of the slide-plate 21 will engage crank-arm 36 and the pressure of spring 27 will be transmitted to rock-arm 28, with the result that feeding pawl 31 will be given a quick feeding movement and a new supply of tape will be advanced within the range of the stitch-forming mechanism of the sewing machine. By adjusting the position of arm 38 on the slideplate 21, the spacing between contact lug 37 and contact finger 38 may be changed to vary the time of action of the feeding pawl or its feeding stroke, as will be understood without further explanation. To prevent any excessive movement of the rock-arm 28 when the same is thrown toward the front of the machine to retract the feeding pawl, a light spring 10 is employed, the said spring being secured at one end to the crank-arm 36 and at its opposite end to an eyed stud 11 projecting from the bracket 19. The tension of spring 40 is not sufficient to advance the pawl when the contact finger 38* moves downwardly, so that the tape will not be acted upon until the knife descends below the upper surface of the throat-plate, and lug 37 meets the crank-arm 36. At the end of the feeding movement of the pawl its ,downwardly projecting lug 35 engages a stud 42 fitted within an aperture formed in the sewing machine frame, whereby the pointed end of the pawl is moved downwardly out of engagement with the tape. As an additional safeguard against movement of the tape during the retraction of the feeding pawl, a holding spring 43 is socured to the under face of the throat-plate. its pronged end extending upwardly through the slot 8 and into engagement with the tape.

From the foregoing it will be seen that the cutter-blade and its actuating and guiding members are connected to a supporting bracket and that the parts may be assembled prior to the application thereof to the machine, and may be removed from the manarrator chine in assembled condition. The tapeguiding elements are supported upon the throat-plate of the machine and comprise two relatively adjustable edge-guiding fin gers and an overlying flat surfaced ledgerblade which is springpresscd to coeperate with the cutter-blade in tape-severing operations. The feeding device for the tape is so arranged with respect to the cutter actuating mechanism that the operative movements of the latter are employed to advance and retract the tape feeding pawl, and means are provided for timing the operative movements of the said pawl so that the same will not act upon the tape until the cutter-blade is withdrawn therefrom.

This invention is of a character susceptibio of various modifications in the form and arrangement of the elements and therefore the same is not limited to the precise embodiment herein shown and described.

Having thus set forth the nature of the invention, what I claim herein is V 1. In tape-cutting mechanism for sewing machines, the combination with a cutterblade and a carrier therefor having a lateral guide-rib, of a supporting bracket formed with an open slot affording spaced arms abutting opposite faces of said carrier, a slide-plate secured to the carrier and confining one of said bracket-arms between its face and the guide-rib of the carrier, an operating lever and a connection between said lever and the slide-plate.

2. In a tape-handlin device, means for shearing tape, including fixed and movable blades, means for feeding tape, a treadleoperable lever for eifecting at will an action of each of said means on the tape, said lever being positively connected with said movable blade and actuating it in opposite directions and positively actuating in opposite directions said feeding means.

3. In tape-cutting mechanism for sewing machines, the combination with the cutterblade and actuating means therefor, of a tape-feeding device including a rock-shaft to which the feeding element is connected, a crank-arm secured upon said rock-shaft, a contact member movable with the cutterblade and adapted to engage said crank-arm and a second contact member movable with the cutter-blade and adjustable relatively to its coacting contact member, whereby the rockshaft is turned in reverse directions by the cutter actuating mechanism to advance and retract the feeding element.

4. In tape-cutting mechanism for sewing machines, the combination with a cutter blade and a carrier therefor, of a supporting bracket provided with arms embracing said carrier, a slide-plate secured to the carrier, an operating lever and a connection between the same and said slide-plate, spaced lugs carried by said slide-plate, a rock-shaft having a crank-arm fitted between the said spaced lugs, a rock-arm secured upon said rock-shaft and a feeding device carried by said rock-arm.

5. In tape-cutting mechanism for sewing machines, the combination with a frame, a cutterblade and actuating means therefor, of a tape-feeding device and an operative connection between said device and the cutter actuating means, a throat-plate mounted on said frame and formed with a transverse receivin slot for the cutter-blade, said throat-p ate being adapted to serve as a tapesupporting member, and-relatively adjustable tape-positioning members carried by said throat-plate.

6. In tape-cutting mechanism for sewing machines, the combination with a frame, a cutter-blade formed with a projecting guidefinger and actuating means for said blade, a tape-feeding device and an operative connection between the same and the cutter actuating means, a throat-plate mounted on said frame and formed with a b1ade-receiving aperture having opposed walls abutting the guide-finger of the cutter-blade, relatively adjustable tape-positioning members carried by the throat-plate and a ledgerblade mounted on the throat-plate and spring-pressed into engagement with the cutter-blade guide-finger.

7. In tape-cutting mechanism for sewing machines, the combination with a cutterblade and actuating means therefor, of a tape-feeding device including a rock-arm and an operative connection between said rock-arm and the cutter actuating mecl1- anisrn, a feeding pawl pivotally supported upon said rock-arm, tape supporting and guiding means, and a stationary stud arranged in and at the end of the path of the feeding stroke of the pawl for rotating said pawl about its pivot to retract it from engagement with the tapeat the end of its feeding movement.

8. In a tape-handling device, means for shearing tape including movable and ledgerblades, a feed point for advancing the tape, a treadle-operable lever positively connected with the movable blade and thereby actuating it in opposite directions, and relatively adjustable lugs movable with the mov able blade for positively advancing and retractin the feed point.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

WILLIAM L. BRON.

Witnesses:

W. Lee Ham/re, II. A. KonNnMANN, Jr. 

